The present invention refers to a device for collecting liquid from exhalation gas from a patient.
The introduction of such devices for the supply of inhalation gas and the removal of exhalation gas, so called intubation, is made as a matter of routine in medical treatment of patients which need external breath support from a respirator. Such devices normally include a plastic pipe, a so called endotracheal tube, which via the throat is guided down into the trachea to a position at the dividing region of the main bronchi. The endotracheal tube is fixed in the trachea by means of a fixing member which is provided slightly above the distal end of the tube and inflated to airtight abutment against the inner wall of the trachea. Air exchange, i.e, supply of relatively oxygen-rich inhalation gas and removal of exhalation gas, takes place through one single channel in the tube, which via an external manifold is connected to the supply outlet and removal inlet, respectively, of the respirator.
The body reacts in a natural way against foreign bodies and organisms, which are present in the airways, by an increased excretion of secretion from the mucous membranes in combination with an increased activity of the cilia. The purpose of the cilia is to catch and transport impurities and secretion out of the body by moving in such a way that they transfer an upwardly directed movement to these impurities and secretion.
When the tracheal tube is installed in the trachea, the cilia may not act any longer in the intended manner since the tracheal tube and the fixing member closes the natural transport way for the secretion, i e the natural cleaning system is by-passed. In addition, the tracheal tubes, which are used today, do not have a satisfactory capability of removing the secretion since the same quantity of gas is transported successively in both directions through the channel of the tracheal tube. Due to these two factors, the secretion and phlegm will be collected in the airways beneath the fixing member. In order not to close off completely the airways by phlegm and thereby prevent an efficient gas exchange, the airways has to be sucked continuously, typically in intervals of 2-3 hours night and days, to drain collected phlegm. Such suction drainage is performed by means of a catheter, which is guided down through the tracheal tube and which, by means of a sub-pressure, sucks secretion to a collecting container. However, suction drainage by means of a catheter is a process which is time-consuming and expensive, and frequently involves complications. Some usual such complications are injuries on the mucus membranes, infections by contamination of the lower respiratory tract, coincident alveoli in the lungs, acute oxygen deficit, heart disorder and unprepared extubation. In addition, the patient is subjected to significant stress, discomfort and a sense of suffocation. There are also other grounds frequently involving pneumonia due to the treatment by conventional endotracheal tubes. Since the fixing member is positioned far down in the trachea in order to minimise the exposure to the secretion producing surface of the trachea, secretion containing bacteria will remain above the fixing member. During exhalation it is not unusual with leakage at the fixing member, wherein contaminated secretion is drawn downwardly into the lungs during the subsequent inhalation.
PCT/SE99/01517 discloses one solution of the problems mentioned above, and more precisely a device, which includes a pipe member intended to be introduced down into trachea of a patient. The pipe member includes a feeding pipe, which has a distal outlet opening arranged to be located at the dividing region of the main bronchi of the patient during use of the device, and a discharge pipe, which has an inlet opening arranged above said outlet opening and through which the feeding pipe extends. By such a pipe member, exhalation gas may be conveyed away from the patient and collected in a container device. The container device may be replaceable and when it is full it may be replaced by a new, empty container device.